Less Is More

Ask a parent or teacher to name the most important factor in
children's learning, and you're likely to hear about small classes. But
ask a principal or superintendent, and you may get a different
response. Administrators sometimes play down the benefits of reducing
the number of students in classrooms. "Research has not conclusively
shown that small classes are linked to improved student learning," they
might say, or "Learning gains only show up when classes get down to 15
kids."

Well, not quite, say researchers from the Student/Teacher
Achievement Ratio project, or Project STAR for short. As part of a
two-phase study, the researchers have been tracking classes of 15 to 17
students in 79 schools scattered across Tennessee since 1985. Their
efforts make up the largest and longest-lasting experiment ever
conducted to examine the effects of small class sizes on student
learning and development.

Not only do students in the early grades learn more in smaller
classes, the project's investigators say. But they continue to have an
edge over the rest of their peers years after they return to
normal-sized classrooms.

What's more, they add, the data they have collected are beginning to
show that every time a student is added to a classroom, learning is
diminished for the rest of the class.

"This is one of the great experiments in education in United States
history," Frederick Mosteller, a Harvard University statistics
professor, says of the proj~ect. "It definitively answers the question
of whether reduction from this size to that size does make a
difference, and it clearly does."

But some education researchers are skeptical that Project STAR's
findings make the definitive case for small classes. They point out
that more than 1,100 studies on class size have been conducted over the
years and that the findings have been mixed.

"I don't think a single study proves all that much," says one such
skeptic, Herbert J. Walberg, a professor at the University of Illinois
at Chicago. "You can find some studies that indicate that bigger
classes have better effects on learning."

Walberg also suggests that other kinds of intervention, such as
cooperative learning, may be more effective and less expensive. Even if
smaller classes do make a difference, critics ask, are they worth the
expense?

Testing It Out

Before Project STAR, the landmark study used to argue for small
classes was an analysis Gene V. Glass and Mary Lee Smith conducted in
the 1970's. They reviewed dozens of studies on the subject and
concluded that reducing the number of students in a class does have a
modest effect on learning.

Their findings also implied that the benefits would not show up
until classes had been reduced to 15 or fewer students. But the study
was controversial, partly because it mixed different grade levels and
kinds of classes, including graduate seminars and one-on-one
tutorials.

When the class-size debate reared its head in the Tennessee
legislature several years later, lawmakers decided to test out the
hypothesis themselves. Spurred by then-Gov. Lamar Alexander's
pro-education agenda, the legislature allocated $3 million to four of
the state's top universities to launch Project STAR.

"All educators and parents know that, with fewer children, you can
do a better job," says Helen Pate-Bain, who lobbied for the project
when she was an associate professor at Tennessee State University. She
says that 30 years of teaching high school taught her that. "But when
you talk to the people who hold the purse strings, they all said to us
that research says that small classes don't make a difference."

"The reason for doing the study was to once and for all show that
class size does make a difference," adds Pate-Bain, who is now retired.
She later became one of four principal investigators in the
project.

Unlike the studies that came before it, Pate-Bain and her partners
wanted Project STAR to be a true experiment in the most scientific
sense of the word. Investigators decided to focus their efforts on
students in kindergarten through 3rd grade, reasoning that small
classrooms could have the biggest effect on young learners.

"If you can give a child a good beginning, if they learn to read,
nobody can take that away from them," says Pate-Bain, who is also a
former president of the National Education Association, which has
pushed hard to make smaller classes part of union contracts.

Of the 79 elementary schools that took part in the study, 25 were
located in urban areas, 16 were in suburbs, and 39 were in rural areas.
To participate, schools had to have at least 57 students in a
grade--enough for one small experimental class of 13 to 17 students and
two normal-sized classes of 22 to 25 students, one with an aide and one
without.

"That way, whatever else might be happening at the school would
happen under all three conditions," says Barbara Nye, who is the
director of a follow-up study that became the successor to Project
STAR.

Students were assigned to their classes randomly.

Through all four years of the study, the researchers found, students
in all four grades on average outscored their peers in both types of
large-class settings on a battery of standardized tests. Those tests
included the Stanford Achievement Test, Tennessee's Basic Skills
Criterion Tests, and another basic-skills-type test developed
especially for the project.

Students in the inner-city schools appeared to make the greatest
leaps. But their counterparts in suburban and rural schools made gains
as well.

In reading and mathematics, the size of the gain was about a quarter
of a standard deviation. To understand what that means, Mosteller says,
think of a child who, without any special treatment, might score at
about the 50th percentile on a test. A gain in score of a quarter of a
standard deviation would raise that child from the 50th to the 60th
percentile. In other words, now 60 percent of the testing population
scored lower than that child.

"And we didn't do anything to schools other than reduce class
sizes," adds Jayne Boyd-Zaharias, who took part in both Project STAR
and the follow-up study.

Having a teacher's aide in the classroom, on the other hand,
produced only slight improvement in student achievement.

But Does It Last?

By the end of Project STAR, researchers had collected data on 7,000
students and spent $12 million. But questions arose over whether the
documented gains would last. So, with continuing support from the
state, the researchers launched a second study.

That project, called the Lasting Benefits Study, is less rigidly
controlled than Project STAR. Through it, however, researchers were
able to track students after they returned to normal-sized classes in
the 4th grade and for years afterward.

In grades 4, 5, 6, and 7, the investigators have thus far found,
students who had been in smaller classes in grades K-3 continued to
outscore their peers who had been in larger classes. The differences in
those scores, however, diminished somewhat as the years went on.

Moreover, the benefits were not limited to reading and math.
Students from smaller classes outscored their grade-mates from larger
classes in science, social studies, and other subjects, too. Other
studies suggest that those students also participated more in class and
took part in more extracurricular activities than their peers from
larger classes.

Researchers are still tracking more than 4,000 of those students and
hope to continue to do so after they leave high school to go on to
college or STARt a career. Results on 8th graders are expected to be
completely analyzed later this year.

Charles M. Achilles, a principal investigator on both projects, is
also analyzing the data to see whether 15 or 17 is a "magic
number"--the threshold at which real learning gains STARt to occur--or
if any reduction in class size helps. Would adding or taking away a
child in a class of 24 or 25 make a difference?

"It looks as though the addition of a child to a class decreases the
class's average scores by about about one-tenth of one month," in terms
of the expected learning progress, he says. But, he warns, "we're still
tinkering with this."

The results from Project STAR and from the early years of the
Lasting Benefits Study persuaded the Tennessee legislature to take the
plunge and pay for small classes. In 1989, lawmakers set aside funds to
reduce class sizes in kindergarten through 3rd grades in 17 of the
state's 138 school districts with the highest proportions of poor
students.

More recently, the American Academy of Arts and Sciences, spurred by
Mosteller's review of the project, has begun to tout the study as proof
that small classes matter. The researchers also traveled to London in
May to present their findings to educators weighing the matter
there.

"It's time that we quit asking the question, 'Does it make a
difference?' and begin to ask why it makes a difference and how we can
begin to use this information," says Achilles, who is also a professor
of educational administration at Eastern Michigan University.

But the question keeps coming up. ERIC A. Hanushek, a University of
Rochester economist and public-policy professor, is one of the critics
to raise it most recently. Hanushek analyzed 300 studies and concluded
that across-the-board reductions in class size are not worth the
expense.

Although Project STAR wasn't included in that analysis, Hanushek
does have an opinion about the study's findings. "Those people are
zealots," Hanushek says of the STAR researchers. The problem with
Project STAR, he explains, is that there is not much "value added"
beyond the achievement gains that come about in kindergarten. The size
of the effect in grades 1 through 3 is about the same.

On the other hand, Hanushek points out, the expense is considerable.
"Dropping a class from 25 to 22 students increases classroom
expenditures by more than 10 percent," he writes in his 1994 book,
Making Schools Work: Improving Performance and Controlling
Costs.

Project STAR's investigators counter that Hanushek, in his analysis,
looked at overall student-staff ratios. That meant he included in his
calculations, for example, librarians and special-education
teachers--neither of which figure much in reducing the actual size of
classes in a given school.

It is true, they concede, that the greatest gains come in the first
year or two that students have smaller classes. But the point, they
say, is that those gains remain just as strong as long as classes
continue to be small.

The researchers also point out that, by 1st grade, the sample of
students in small classes included students who were retained as well
as 250 students who had not gone to kindergarten. (Kindergarten
attendance was not mandatory in Tennessee at the time.) If anything,
the STAR researchers say, their numbers are probably conservative.

They also suggest that, contrary to what Hanushek says, the benefits
are cumulative. In kindergarten, 55 percent of the top-scoring classes
in the project's sample population were small classes. By 3rd grade,
small classes accounted for 78 percent of the top 10 percent.

As for the cost, the STAR researchers point out that reducing the
number of students that are held back each year or that require
remedial service through the federal Title I program for disadvantaged
students translates to cost savings in the long run.

"Is it worth it to spend $1,500 extra for a child not to fail," Nye
asks, "rather than spend $10,000 for a child to repeat a grade?"

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